1. Field of the Invention
Aspects of the present invention relate to magnetron sputtering equipment, and more particularly, to a magnetron unit moving apparatus capable of spacing a target and a magnetron apart so as to prevent magnetization, and a magnetron sputtering equipment having the magnetron unit moving apparatus.
2. Description of the Related Art
As shown in FIG. 1, a magnetron sputtering apparatus generally includes a vacuum chamber 10, a supply pipe 11 of an inert gas (such as argon) connected to the vacuum chamber 10, a vacuum pump (not shown) connected to the vacuum chamber 10 through an exhaust pipe 12, a chuck 20 and a target 30 disposed to face each other in the vacuum chamber 10, and a high-frequency power supply 14 to apply a high frequency to the chuck 20. The high-frequency power supply 14 is connected with the chuck 20 through an electrode 13.
A magnetron unit 40 that can provide a magnetic field required for a process to the target 30 is installed in the vacuum chamber 10. The magnetron unit 40 includes a magnet 42 and a fixing plate 41 that fixes the magnet 42, and is disposed above the target 30. The target 30 and the magnet 42 are spaced apart by a predetermined and fixed distance D when they are installed.
In the magnetron sputtering apparatus, a substrate 21 is placed on the chuck 20. Argon is supplied into the vacuum chamber 10 through the supply pipe 11. The vacuum pump is operated to exhaust the gas in the vacuum chamber 10, such that a vacuum degree required for a process is achieved in the vacuum chamber 10. Subsequently, a high frequency is applied to the chuck 20 from the high-frequency power supply 14, and thus plasma is generated between the substrate 21 and the target 30. Direct current (DC), alternating current (AC), a radio frequency (RF), pulsed DC, a mid-frequency, a very high frequency (VHF), etc., can be applied to the chuck 20.
The plasma activates the argon, and the activated argon collides against the target 30, to which a ground voltage or a negative voltage is applied, and sputters the target 30. The particles of a target material sputtered due to a specific magnetic field generated from the target 30 move to the surface of the substrate 21. The sputtered particles of the target material accumulate on the surface of the substrate 21, such that a layer of the target material is formed on the substrate.
Conventionally, the above-described sputtering method is frequently used to crystallize polysilicon using a metal catalyst. The sputtering method is suitable for forming a layer on a large area of the substrate 21, and facilitates control of the amount of deposited metal, such as nickel, according to process control. According to super grain silicon (SGS) crystallization, however, a small amount of metal equal to or less than a specific amount must be deposited, unlike metal induced crystallization (MIC) or metal induced lateral crystallization (MILC). Thus, SGS crystallization has a problem in deposition uniformity and deposition rate control.
The conventional magnetron sputtering equipment has the magnetron unit 40 that generates the specific magnetic field above the target 30. In addition, the magnetron unit 40 and the target 30 are spaced apart by the specific distance D. For example, when a sputtering process is performed, the magnetron unit 40 controls the deposition uniformity and deposition rate of the target particles on the substrate 21 while generating a magnetic field of 200 to 800 gauss toward the target 30.
However, the conventional magnetron unit 40 is kept apart from the target 30 by the distance D even after the sputtering process is finished, and thus the target 30 formed of a magnetic material or a magnetizable material is magnetized. When the target 30 is magnetized to a specific gauss or more as mentioned above, the magnetic field generated over the target 30 during the process may be distorted. As a result, the deposition uniformity of the target particles deteriorates due to the magnetization of the target 30, thus resulting in quality deterioration of a product.